#ifndef __FILE_LIST_H__
#define	__FILE_LIST_H__


struct list_head {
	struct list_head *next, *prev;
};

#define LIST_HEAD_INIT(name) { &(name), &(name) }

#define LIST_HEAD(name) \
	struct list_head name = LIST_HEAD_INIT(name)

#define INIT_LIST_HEAD(ptr) do { \
								(ptr)->next = (ptr); (ptr)->prev = (ptr); \
							} while (0)

static  void __list_add(struct list_head * new, struct list_head * prev, struct list_head * next);
static  void list_add(struct list_head *new, struct list_head *head);
static  void list_add_tail(struct list_head *new, struct list_head *head);
static  void __list_del(struct list_head * prev, struct list_head * next);
static  void list_del(struct list_head *entry);
static  void list_del_init(struct list_head *entry);
static  int list_empty(struct list_head *head);
static  void list_splice(struct list_head *list, struct list_head *head);

#define list_entry(ptr, type, member) \
	((type *)((char *)(ptr)-(size_t)(&((type *)0)->member)))

#define list_for_each(pos, head)\
	for(pos=(head)->next; pos != (head); pos = pos->next)

/* malloc分配内存 */
#define NEW_LIST_NODE(type, node) \
{\
	node = (struct type *)malloc( sizeof(type)); \
	if (node == NULL) exit(-1);\
}

#define FREE_LIST(type, p, list_name)\
{\
	struct type  *posnode;\
	while(!list_empty(&(p)->list_name)) {\
		posnode = list_entry((&(p)->list_name)->next, type, list_name);\
		list_del((&(p)->list_name)->next);\
		free(posnode);\
	}\
}

/*
 * 通用链表实现部分
 */
static  void __list_add(struct list_head * new, struct list_head * prev, struct list_head * next)
{
	next->prev = new;
	new->next = next;
	new->prev = prev;
	prev->next = new;
}

static  void list_add(struct list_head *new, struct list_head *head)
{
	__list_add(new, head, head->next);
}

static  void list_add_tail(struct list_head *new, struct list_head *head)
{
	__list_add(new, head->prev, head);
}

static  void __list_del(struct list_head * prev, struct list_head * next)
{
	next->prev = prev;
	prev->next = next;
}

static  void list_del(struct list_head *entry)
{
	__list_del(entry->prev, entry->next);
}

static  void list_del_init(struct list_head *entry)
{
	__list_del(entry->prev, entry->next);
	INIT_LIST_HEAD(entry);
}

static  int list_empty(struct list_head *head)
{
	return head->next == head;
}

static  void list_splice(struct list_head *list, struct list_head *head)
{
	struct list_head *first = list->next;

	if (first != list) {
		struct list_head *last = list->prev;
		struct list_head *at = head->next;
		first->prev = head;
		head->next = first;
		last->next = at;
		at->prev = last;
	}
}

#endif	/* __FILE_LIST_H__ */
